https://github.com/MicrosoftDocs/mslearn-typescript/blob/10bb2e38ee5559dae2ebe351d5fda05517615262/code/module-05/m05-end/module05.ts#L52 ` nextNumber = Math.floor(Math.random() * 100) + 1 ` This will give a random number between 1 and 100 , with both boundaries , the 1, and the 100 included